Twisted pair cables are commonly used for the wiring of computer and telephone networks. Twisted pair wire orientation is governed by EIA/TIA Standard 568B and industry connection methods
Conventional twisted pair cable includes four twisted pair conductors inside an outer insulation jacket. In some cables a plastic cross shaped extrusion resides inside the cable jacket along with the wires to separate the four pairs from each other and maintain each pair within its own quadrant within the cable jacket.
The four twisted pairs are color coded as a blue pair, a green pair, an orange pair, and a brown pair. Each pair includes two conductors a first conductor covered by solid color insulation colored to match that pair designation and a second conductor covered by white insulation with colored stripes that are the same color as the solid colored insulation twisted together. For example, the blue pair includes one wire solid blue in color and a second wire white with blue stripes. The same is true for the green, orange, and brown pairs. In the 568B standard, the color coding standardizes the position each conductor occupies when assembled into an RJ45 modular connector or modular jack.
There are 8 positions in a modular connector, one for each conductor. A prior art RJ45 plug includes a front where it mates with a jack and a rear where the cable enters as well as a locking tab. Viewing the front of the RJ45 plug, with the locking tab at the top, the eight positions are designated one through eight from left to right. Under the standard, the blue pair typically is designated Pair #1 and occupies position 4 and 5 with the solid blue conductor in position 4 and the white/blue conductor occupies position 5. The Orange pair is designated Pair #2 and occupies positions 1 and 2 with the white/orange conductor in position 1 and the Orange conductor in position 2. The green pair is designated Pair #3 and is also known as the split pair in the RJ45 assembly because it occupies positions 3 and 6 with the solid green conductor in position 6 and the white/green color conductor occupying position 3. The brown pair is designated Pair #4 and occupies positions 7 and 8. The white/brown conductor is located at position 7 and the solid brown conductor in position 8. The importance of these standardized positions will become apparent in the description of the sub components and assembly of the new connector of the present invention.
The most dominant interface for connecting 4 pair twisted pair cable in the market at the time of this application is the RJ45 connector interface as described by the FCC in 47 CFR 68 Subpart F. The FCC standard describes dimensional tolerances for the plug, port and features to assure operable compatibility between plugs and jacks made by various manufacturers.
Typically an industry standard modular jack has one port for mating with an RJ45 plug, that meets the requirements of FCC under 47 CFR 68 Subpart F and a second port that is adapted to attach twisted pair cable conductors to the jack. Generally, jacks are terminated to twisted pair cable in the field by stripping back the outer jacket, exposing the conductor pairs, and terminating these pairs to terminals on the jack. Patch cords in predetermined lengths, with RJ45 plugs assembled to each end, are available to connect hardware such as computer work stations and printers to the modular jacks and thus to the network.
In many cases, the modular connector is installed by craft personnel in the field. Problems are associated with installing jacks and plugs in the field related to inconsistency of method that occur from one installer to the next. These result is failures in data transmission and the expenditure of large amounts of time and effort to troubleshoot and repair inadequate field made connections.
One possible solution to this problem would be to pre-terminate the connection in a controlled environment and to test the connections prior to installation in the field. The obstacle to pre-terminating all connections lies in the need to feed and pull cable with plugs installed through conduit and around obstacles common in buildings being wired for networks. The design profile of the prior art RJ45 modular plug is too large to be pulled through smaller conduit channels and the features, such as the locking tab, and shape of the plugs make them prone to catch on obstacles. This leads to damage to the connectors and cable.
Thus the network wiring industry would benefit from a network wiring termination system that that would allow for pre-termination of conductors, testing of the network wiring components prior to release to field personnel and ease of pulling network wiring through conduit and past obstacles that are commonly encountered in the installation of network cabling.